Body armor should be taken care of just like anything else; not many realize that it has a lifespan, and improper care will only reduce that lifespan. Body armor has a warranty of 5 years, and while the materials themselves have a much longer lifespan, old and faulty armor should be replaced. Of course, if it is damaged in any way it should not be worn and should be replaced immediately. This is why it is so important to properly take care of armor, including checking it thoroughly before wearing it.
Armor should be treated as clothes are treated; it should be regularly washed and properly stored. The carrier is machine washable, but the ballistic plates in the vest should only be washed gently with a sponge and a mild cleaning agent. It is recommended that you own multiple carriers, and possibly even multiple plates, to ensure that you always have clean and dry armor to wear. It is very important to be careful when washing your ballistic or stabproof plates, as exposing them to high temperatures may cause them to warp and lose their effectiveness. Similarly, submerging your armor in water will ruin its effectiveness, which is why it should only be washed gently with a sponge. If your plates do appear to be deformed in any way, they should not be used. Similarly, armor should be kept flat in a cupboard or drawer where it will not be folded or crumpled, and will not have heavy objects on top of it.
Carefully cleaning, storing, and checking your armor will help a great deal in extending its lifespan to the maximum. It also ensures that you are not wearing dirty or damaged armor, which at best may ruin your clothes, and at worst may no longer protect you from a potentially fatal attack.